18z Model Thread 12/22

[yoda]

SNOW INTO cent va nc by midday christmas much faster this run wit the low

hr 78 sub 1012 over southern ga.. precip almost up to dc

[Gibbsfreeenergy]

84hrs 6mb deeper vs 12z same time.. along SC coast

[baroclinic_instability]

This looks very CMC'ish from a couple days ago. Looks good though through 72.

[MN Transplant]

RH field much more robust at 700.

[Gibbsfreeenergy]

995mb just offshore hse! another solid trend here!!

[yoda]

hr 90 sub 996 50 miles east of hse

[eurojosh]

Question - does the GFS have an increased bias towards climo in the North western hemisphere? I'm wondering if the reason the Euro has been better in December - I mean, significantly better - is because it works off a climo model that is less defined, particularly for this quadrant?

Or maybe this question would be worth waiting 6 days to ask...

[baroclinic_instability]

This is a potential big one. Looks very close to Euro if it hooks more through 90.

[Terpeast]

NCEP is not updating. Trying to look at raleighwx site but slow going.

[stormtracker]

This is a potential big one. Looks very close to Euro if it hooks more through 90.

Good words from baroclinic_instability?!?!? Whoa

But yeah, this sounds like a solid trend toward the Euro

[baroclinic_instability]

Exactly the same as 12Z but weaker and faster. No cigar yet.

[dg12x]

Use http://www.meteo.psu.edu/~gadomski/ewall.html

[PhineasC]

Seems a bit east of Euro still, but clearly the GFS is moving towards that solution much more than away from it.

[yoda]

hr 99 sub 984 bout 150-200 miles east of mouth of ches bay...coastal area getting some mod preicp

its exactly like the 12z basically despite the better changes at h5. Reason why its way faster than 12z...you slow this to 12z gfs speed this would be closer to the coast

[tombo82685]

Exactly the same as 12Z but weaker and faster. No cigar yet.

h5 changes changes were for the better. You slow the 18z solution to the 12z gfs speed and you would get a storm closer to the coast imho.

[needbiggerboat]

18z dgex ots, fwiw (not much)

[stormtracker]

And its moving ever closer. This one is the real deal. Precip still kinda sucks on the back side tho

[Gibbsfreeenergy]

Despite the early track changes, actual track very close to 12z sfc low track. Altho the upper pattern looked much better to me and would think 18z would have been west of 12z given how capatured it looked.

[earthlight]

Ridiculously close to the Euro..it just lets it scoot a bit east. Seems to be near the Euro ensemble track and in line with the GGEM. Also seems a bit faster

[33andrain]

Looks like it's about 6 hours faster and a bit NW

[PhineasC]

18z dgex ots, fwiw (not much)

It is worth nothing. Please people, stop posting the DGEX. It is terrible.

[baroclinic_instability]

A thought for other mets. Convection and very mesoscale forcings are going to play a prominent role in this somewhat compact system. Will be interesting to see if the Euro's decided advantage in resolution plays a role, even after the GFS upgrade.

[Gibbsfreeenergy]

ends up just being faster with less precip and not as deep

[baroclinic_instability]

And its moving ever closer. This one is the real deal. Precip still kinda sucks on the back side tho

Yeah agreed, even though the surface track is quite similar and a tad weaker, the upper air charts are more favorable. A good step indeed.

[NaoPos]

Phases @ 72....

Goes Negative 84-90

and still doesn't close off at h5 till 102 untill it's east of lewes delaware.

anyone else think that seems a bit slow considering the amount of energy being absorbed by the trough? or does that seem reasonable? ( interms to the overall outcome)

[earthlight]

Yeah agreed, even though the surface track is quite similar and a tad weaker, the upper air charts are more favorable. A good step indeed.

Yeah. The first thing I thought when I saw the 102hr panel was "almost there". I suspect that, if all goes well, we will see another nudge west on the 00z suite..which is tremendously important with the shortwave coming ashore. I'm not sure if it will get on land by 00z but it will certainly be very close.

[baroclinic_instability]

Yeah. The first thing I thought when I saw the 102hr panel was "almost there". I suspect that, if all goes well, we will see another nudge west on the 00z suite..which is tremendously important with the shortwave coming ashore. I'm not sure if it will get on land by 00z but it will certainly be very close.

Yeah it was so close Looking at 96 at the upper air chart, it has room to hook NW. Look at the blob of convection tracking NE, the GFS really has that overcoming the synoptic forcings/mesoscale jet circulation wanting to hook into the coast. I throw the thought out there, but there is an outside shot ECM is more right simply because of its horizontal resolution (spectral wave) alone and that it can better handle the meso forcings and possibly convection--all of which will play a very prominent role in a rapid feedback cyclone such as this.

[winterymix]

And its moving ever closer. This one is the real deal. Precip still kinda sucks on the back side tho

I think the GFS surface reflection doesn't match the 700 mb. It makes no sense that the west side should be

nothing but virga with all of the Atlantic moisture being tapped.

[earthlight]

Yeah it was so close Looking at 96 at the upper air chart, it has room to hook NW. Look at the blob of convection tracking NE, the GFS really has that overcoming the synoptic forcings/mesoscale jet circulation wanting to hook into the coast. I throw the thought out there, but there is an outside shot ECM is more right simply because of its vertical resolution (spectral wave) alone and that it can better handle the meso forcings and possibly convection.

The Euro has had this solution, or something with big coastal impact, for six runs in a row now. The GFS has trended towards it slowly..I would like to see some signals on the GFS Ensembles in a few minutes when the mean comes out.

In about 12-24 hours..if the current modeling holds and the Euro doesn't get flat..I will ring the dinner bell. The Euro very rarely gives off an alarm like this and it's doing it right now. I can't even begin to count the amount of times I have seen the GFS be slightly southeast and less amplified than the Euro at 102 hrs only to come northwest as the storm approached.

That being said..this is a very fragile setup. I've said it several times. Somebody can sneeze near the MS river and mess up the phase. So we can hope the Euro's vertical resolution is helping it resolve the differences here. But I would hope some globals start trending west soon; otherwise the Euro will begin to become an obnoxious outlier.

[Gibbsfreeenergy]

Yeah agreed, even though the surface track is quite similar and a tad weaker, the upper air charts are more favorable. A good step indeed.

the upper air at 90hrs and what occurs with sfc low post 90hrs seems like a disconnect a bit.

in comparing the 18z op gfs to the 12z ec, pretty darn close with all major vorts...biggest difference I see is north of the Great Lakes in Ont with GFS having vortex farther south and east. then by 6z sunday the 18z op gfs allows for more energy to dig toward MSP as opposed to euro keeing a more more North to south flow there. those small differences look to alter the sharpness/broadness of the over mean trof and affect the timing and amplitude with which features phase